// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Video capture interface for Linux version 2
*
* A generic video device interface for the LINUX operating system
* using a set of device structures/vectors for low level operations.
*
* Authors: Alan Cox, <alan@lxorguk.ukuu.org.uk> (version 1)
* Mauro Carvalho Chehab <mchehab@kernel.org> (version 2)
*
* Fixes: 20000516 Claudio Matsuoka <claudio@conectiva.com>
* - Added procfs support
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/debugfs.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/kmod.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <media/v4l2-common.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-event.h>
#define VIDEO_NUM_DEVICES 256
#define VIDEO_NAME "video4linux"
#define dprintk(fmt, arg...) do { \
printk(KERN_DEBUG pr_fmt("%s: " fmt), \
__func__, ##arg); \
} while (0)
/*
* sysfs stuff
*/
static ssize_t index_show(struct device *cd,
struct device_attribute *attr, char *buf)
{
struct video_device *vdev = to_video_device(cd);
return sprintf(buf, "%i\n", vdev->index);
}
static DEVICE_ATTR_RO(index);
static ssize_t dev_debug_show(struct device *cd,
struct device_attribute *attr, char *buf)
{
struct video_device *vdev = to_video_device(cd);
return sprintf(buf, "%i\n", vdev->dev_debug);
}
static ssize_t dev_debug_store(struct device *cd, struct device_attribute *attr,
const char *buf, size_t len)
{
struct video_device *vdev = to_video_device(cd);
int res = 0;
u16 value;
res = kstrtou16(buf, 0, &value);
if (res)
return res;
vdev->dev_debug = value;
return len;
}
static DEVICE_ATTR_RW(dev_debug);
static ssize_t name_show(struct device *cd,
struct device_attribute *attr, char *buf)
{
struct video_device *vdev = to_video_device(cd);
return sprintf(buf, "%.*s\n", (int)sizeof(vdev->name), vdev->name);
}
static DEVICE_ATTR_RO(name);
static struct attribute *video_device_attrs[] = {
&dev_attr_name.attr,
&dev_attr_dev_debug.attr,
&dev_attr_index.attr,
NULL,
};
ATTRIBUTE_GROUPS(video_device);
static struct dentry *v4l2_debugfs_root_dir;
/*
* Active devices
*/
static struct 